J. David Rogers, Ph.D., P.E., R.G., C.E.G.
Karl F. Hasselmann Chair in Geological Engineering
Department of Geological Sciences & Engineering
Missouri University of Science & Technology
129 McNutt Hall, 1400 N. Bishop Ave.
Rolla, MO 65409-0230


Taken from: Forensic Geology, by Raymond C. Murray and John C.F. Tedrow (1992)

First criminal case using earthen materials as evidence

In October, 1904, a forensic scientist in Frankfurt, Germany named Georg Popp was asked to examine the evidence in a murder case where a seamstress named Eva Disch had been strangled in a bean field with her own scarf. A filthy handkerchief had been left at the scene and the nasal mucus on the handkerchief contained bits of coal, particles of snuff, and, most interesting, grains of minerals, particularly the mineral horneblende. A suspect by the name of Karl Laubach was known to work in a coal-burning gasworks and part-time in a local gravel pit. Popp found coal and mineral grains, particularly the mineral horneblende, under the suspect’s fingernails. It was also determined that the suspect used snuff. Examination of soil removed from Laubach’s trousers revealed a lower layer in contact with the cloth whose minerals compared with those found in a sample collected from the place where the body of Eva Disch had been found! Encrusted on top of this lower layer a second soil type was found. Examination of the minerals in the upper layer revealed a mineralogy and size of particle, particularly a crushed mica grain, that Popp determined were comparable with soil samples collected from the path that led from the murder scene to the suspects home. From these data is was concluded that the suspect picked up the lower soil layer at the scene of the crime and that this lower, thus earlier material, was covered by splashes of mica-rich mud form the path on his return home. When confronted with the soil evidence, Karl Laubach admitted the crime and the Frankfurt newspapers of the day carried headlines such as “The Microscope as Detective.” It is impossible to determine from the distance of almost a century how a forensic geologist or a jury today would evaluate the geologic evidence amassed by Popp. One fact is evident, mineral study had been used in an actual case, fulfilling the prophesy of Arthur Conan Doyle who had hypothesized the use of geology in criminalistics when he penned the Sherlock Homes mysteries between 1887 and 1893.

Layers of dirt leave a clear trail – the Filbert case (1908)

The case that established the value of geologic information occurred in the spring of 1908. Margarethe Filbert was murdered near Rockenhausen in Bavaria. The district attorney in Kaiserslautern, a man by the name of Sohn, was seeking information on the source of some hairs found in the victim’s hands. He was familiar with Hans Gross’s text Handbook for Examining Magistrates (1893) and had filed, for future reference, clippings from the Frankfurt newspaper of 1904 describing Georg Popp’s work in the Disch case. District Attorney Sohn located Popp in Frankfort and asked him to study the hair and other material.

Georg Popp began and intensive study of the available material. He studied the hair and concluded that it came from the victim. Not easily discouraged, he extended his studies to other objects, noting with special interest encrusted soil on the dress shoes of the principal suspect, a local factory worker and farmer named Andreas Schlicher. Schlicher was a person of “low reputation who had previously been suspected of poaching.” Following the murder, many of his neighbors had suggested him as a likely suspect. It had been established that Schlicher’s wife had cleaned his dress shoes the night before the murder and that he had worn them only on that day. However, he stoutly denied having anything to do with the crime or having walked on that day in the field where the crime was committed. His trousers had been found in a nearby abandoned castle along with a rifle and ammunition used in poaching. It was established that the ammunition was his. However, he claimed that they had been left at the castle prior to the day of the murder.

Popp collected soil samples from the surrounding area. He studied these, assisted by a geologist by the name of Fischer, and observed that the area immediately surrounding the suspect’s home was littered with green goose droppings. The fields of the suspect contained a distinctive soil containing fragments of porphyry, milky quartz, and mica. Root fibers, weathered straw, and leaves were also common. Most interesting was the observation that the scene of the crime had a soil containing decomposed red sandstone, angular quartz, ferruginous clay, and little vegetation. At the castle where the trousers and gun were found, the soil contained coal, abundant brick dust, and broken pieces of cement from the crumbling walls.

Upon examining the dress shoes of the suspect, Popp was impressed with the thickly caked soil on the sole of the shoes in front of the heel. He reasoned that the soil must have accumulated as the suspect walked on the one day he had worn the shoes. That one day was the day of the murder. In addition, he reasoned that the layers of soil that accumulated on the shoes represented a sequential deposit, with the earliest material deposited directly on the leather. Careful removal of the individual layers revealed the following sequence: First a layer of goose droppings directly on the leather followed by grains of red sandstone. A mixture of coal, brick dust, and cement fragments rested on top of the sandstone. In all three layers, Popp was able to compare the material on the shoe with the soil from near the suspect’s home, the scene of the crime, and the castle. Although Schlicher had claimed he had walked in his own fields, no fragments of porphyry with milky quartz were found on the shoes. The comparison of the soil on the shoes with the scene of the crime and the scene where the trousers were discarded indicated that the suspect had lied and had been at these places on the day of the crime.
Georg Popp made many contributions to forensic science. However, the Margarethe Filbert case established him in the field of forensic geology and set the stage for later studies of soil comparison. In this early case, he had established a time sequence of soil accumulation representing the places where a person had walked. Hans Gross had been right. The dirt on the shoes had told more than had been obtained from intensive interrogation.

Traces of red face powder beneath a suspect’s fingernails (1912)

In 1912 Emile Gourbin was a bank clerk in Lyons, France. He came under suspicion of murdering, by strangulation, his girl friend, Marie Latelle. Gourbin was arrested but produced what appeared to be an air-tight alibi. Locard went to Gourbin’s cell and removed scrapings from under his fingernails. These scrapings contained tissue that might have come from Marie’s neck, but this was not provable. Locard noticed that the tissue was coated with a pink dust, which he identified as rice starch. On the particles he found bismuth, magnesium stearate, zinc oxide, and a reddish iron oxide pigment, Venetian red. Examination of the face powder used by Marie revealed that a powder prepared for her by a Lyons druggist was similar in composition. In these days of mass-produced face powder, this evidence would have far less significance. However, in 1912, because of the special preparation, it led to the confession of Gourbin.

Beach sand and the murder of Father Heslin (1921)

In the United States, the small town of Colma, California was shocked when, on the night of August 2, 1921, the parish priest, Father Patrick Heslin, was kidnapped. A ransom note was received, but no further contact was made and the priest was assumed to have been murdered. In a remarkable bit of genius or luck, U.C. Berkeley chemistry professor Edward Heinrich examined handwriting on the note and announced to the police that the writer “had the hand” of a baker and decorator of cakes. Thus, when William Hightower reported to the police that he had heard where the body of Father Heslin was buried, they were immediately suspicious that he might know more than he admitted. Hightower was a master baker.

Heinrich examined the place on the California beach where Hightower indicated the body of Father Heslin would be found. The body was found and the investigation also produced a number of objects of physical evidence, such as boards from a tent floor. Heinrich studied grains of sand recovered from Hightower’s knife and pronounced them similar to the sand on the beach where the body was found. In Hightower’s room a tent was found, and the tent contained an abundance of sand, which, when studied, confirmed the results from the knife. It appeared that Hightower had kidnapped and murdered Father Heslin and kept his body in the tent on the beach for several days before burying it in the sand. Having done these things, he then reported to the police having received information about the location of the body. Hightower’s trial resulted in conviction and he was sentenced to life imprisonment at San Quentin Penitentiary.

Grains of Merritt Sand point to another location 12 miles away (1925)

In 1925, Edward Heinrich undertook an intriguing case to which he would apply his knowledge of geology. Mrs. Sideny d’Asquith, sometimes known as Mrs. J.J. Loren, had been murdered and her body dismembered. Parts of her body, including an ear, were found in a marsh near El Cerrito, California. The rest of the body could not be found despite an intense search. Heinrich determined that the grains of sand he found on the ear of the victim did not come from the black mud of the marsh and reasoned that the body with the ear attached had been placed elsewhere. Later the ear with the sand grains from the earlier location and part of the head had been removed and taken to the marsh. He studied the sand grains, noting their size and composition. He also observed that they had what he considered insufficient salt crystals adhering to them to have been sand from an ocean beach. There was some salt present and he deduced that it came from a river or brook at a place where it entered the ocean. He studied maps with the assumption that he was looking for the nearest place to the marsh where such conditions exist. The place he suggested was Bay Farm Island, 12 miles from the marsh at El Cerrito, near the mouth of San Leandro Creek. Despite some doubts, a search was instigated at Bay Farm Island and the rest of the body was found buried under the drawbridge between Alameda and Bay Farm Insland. The case has never been solved. However, the combination of skill, and perhaps luck, that Heinrich employed introduced forensic geology to the United States in a most dramatic way.

Dredged soil placed in landfill leads investigators to murder site

For example, when an exhumed, unembalmed body was discovered one morning in a common green plastic garbage bag on a police pistol range in an eastern city, it was assumed that someone was trying to give someone else a message. Only the dirt in the bag that had been dug up with the body potentially tied that body to the original burial site and to those responsible. Detailed examination of the soil provided information that led to outlining on a Soil Conservation Service map areas where that type of soil was found. The soil was interesting and could be shown to have been material dredged up from a nearby bay to create landfill. In addition, the landfill could have been no more than a few years old. With this aid to the investigation and assistance from informers, the original burial site was located under the front porch of a home recently built on landfill. Comparison of the soil from that location with samples associated with the body provided evidence that helped tie the body to the original burial site. It actually turned out to be a “family affair,” in that the mother and daughter had murdered the father and buried him underneath the front porch. Distressed with the smell, they dug up the body one night and dropped it in the only wooded area in town – the police pistol range. This example represents the use of soils as both an aid to an investigation and then the follow-through when the soil becomes actual evidence once soil samples from the crime scene are available for comparison.

Commercial sand from a construction site

In another example, in southern Ontario a man was arrested and charged with the beating death of the young girl. The scene of the crime was a construction site adjacent to a newly poured concrete wall. The soil was sand that had been transported to the scene for construction purposes. As such, the sand had received additional mixing during the moving and construction process and was quite distinctive. The glove of the suspect contained sand that was similar to that found at the scene and significantly different in composition and particle size from the area of the suspect’s home. This was important because the suspect claimed the soil on the gloves came from his garden.

Thievery of Cacti from federal lands in southern Arizona

Believe it or not, larceny of cacti is big business. Did those giant cacti in the landscaping of an expensive southern California home once grow on federal land in Arizona? The only physical evidence tying the cacti to federal land was the dirt attached to the roots. Thieves obtained a bill of sale for hundreds of cacti from a cooperating private landowner. They then moved on to federal land and dug up the cacti. Once on the highway, they had the plants and a bill of sale. Who was to say that the cacti were not legally removed from the private land and were being legally transported to a large city for sale to landscapers or private individuals? How do you prove theft of federal property? Without knowing the exact locations where the cacti were removed from federal property, it was impossible to compare the dirt on the roots of the cacti with samples from specific locations. However, it is sometimes possible to demonstrate that the dirt from the roots could not have come from the land indicated on the private bill of sale. Armed with this information, investigators may be successful in inducing one or more of the participants to inform them of the true location of the theft so that soil samples can be collected from the actual holes in the ground where the cacti were removed. This permits comparison between those soil samples and soil collected from around the roots of an individual cactus and offers the possibility of tying specific cacti to their original growing locations on federal land. Such evidence is useful in demonstrating the theft of government property and causing the ultimate appearance of the thieves in a federal courtroom.

Theft of artifacts from federal lands

Recently there have been several similar cases involving excavation and theft of archeological materials from federal land. In one case, a pottery shard from the archeological site was physically fitted back together with another shard that was in the possession of the suspect. Several cases exist where soil encrusted on projectile points, clothing, and pottery found in the possession of suspects compared with soil samples collected at the site of the excavation. In a case involving the theft of ancient baskets from the Manti-La Sal National Forest in eastern Utah, Dr. Jack Donahue and his colleagues were actually able to collect small samples of soil from under the stitching of the baskets, despite the fact that the suspect had thoroughly cleaned them. Faced with the evidence from the soil analysis, the suspect confessed to the crime. In cases of this type, it is usually critical to establish that the material was removed from federal land and not obtained from private land with permission, as claimed by the suspects.

Testing an alabi

In an exemplary case, an elderly woman was mugged and murdered in a Washington, D.C. park some years ago and her body was found under a park bench. Within a short time, a suspect was apprehended as a result of a description given by a witness who had seen the person leaving the park on the night of the murder. It was obvious that the suspect had been involved in a struggle, and he has soil adhering to his clothing and filling his trouser cuffs. He claimed to have been in a fight in another part of the city and gave the location of the fight. Study of the soils near the park bench and of those collected from the scene of the alleged fight revealed that the soil from the suspect’s clothing compared with that near the park bench, and not with samples from the area of the described fight. The comparable similarity with the soil sample from the park area strongly suggested that the suspect had been in contact with the ground in that area and cast strong doubt on his statement that he had not been in the park for years. Furthermore, the lack of similarity between the clothing soil samples and those from the area where he claimed to have been fighting questioned the validity of his alibi.

Hit-and-Run auto from the Missouri lead-zinc mining belt

In another case, the soil dislodged from the fender or frame of an automobile during a hit-and-run accident provided a clue to the area where the car had been driven and thus the possible home or past driving area of the person responsible. In the case of a fatal hit-and-run accident in the upper Midwest, clumps of soil dislodged from the fender of the car as it struck the victim and sped away were shown to contain the characteristic minerals of the Missouri lead-zinc mining district hundreds of miles to the south. This knowledge contributed to the successful search for a suspect. When the suspect was apprehended and soil from under the fenders of his car was studied, it was found to compare with the material collected from the highway at the scene of the crime. Furthermore, it was subsequently shown that he had previously driven though mining areas of Missouri where rocks from the mines (chat) are used as road bed material.

Ballasts rocks tell where crime was committed

In another case, rocks were substituted for valuable articles in boxes that were in transit and provided a clue to the place where the switch was made by determining where the rocks originated. When a Canadian liquor store owner opened newly arrived cases of Scotch whiskey and prepared to place the bottles on the shelf, he was unpleasantly surprised to find blocks of limestone, each of which was of the same weight as a bottle of whiskey, neatly placed in each compartment. From a study of the limestone, it was determined that it could not have come from any of the places through which the whiskey passed in transit, other than from its point of origin in Great Britain. Further study revealed that the limestone in the boxes compared with limestone from a particular quarry in central England and, finally, that the suspect, who worked for the liquor distributor and had immediate access to that quarry, had often been seen taking home many samples of the rock.

Foreign object infiltration ignites gunpowder plant

In the case of an explosion that destroyed part of a plant that manufactured smokeless powder, an unusual rock provided information that was useful during the investigation. In this plant, the powder was extruded from a press, and the extruded rods were cut to the desired length. The explosion occurred in the press. After the explosion, an experienced investigator found several small rocks on a screen that was part of the press. They had been in the explosion and must have been mixed into the batch of powder that exploded when squeezed in the press. The presence of these foreign objects in the powder was presumed to have been responsible for the explosion. Rocks with a hardness of greater than approximately 2.5 on the Moh’s hardness scale and having a melting temperature of greater than 500?C appear to be able to produce sufficient frictional heat to detonate some explosives. These rocks met those specifications. The investigators then faced the question of whether the rocks were placed in the powder deliberately or by accident. The question was asked, “ Where did the rocks come from?” This plant had areas of walks, parking areas, and lawn containing many different kinds of rocks, both local and those brought there as cover for paths and aggregate.
The rock fragments removed from the site of the explosion contained the uncommon feldspar mineral aventurine, sometimes called sunstone. Although rare, it is quite distinctive and easily recognized. Careful study of the plant area located the place where similar rocks were found. This information was used in the investigation and particularly during the interrogation of suspects about their movements around the plant area prior to the explosion.

Cattle rustlers nabbed by Missouri chert

The appearance of a rock in an area where it could not have originated often leads to substantial evidence. A herd of prize cattle was stolen from a farm in south central Missouri and was suspected of having been transported to a ranch in Montana. The brands had been altered. However, the owner was positive that he recognized his cattle on the suspect’s Montana ranch. An examination of the bed of the cattle truck owned by the suspect revealed abundant fragments of chert, a chemical sedimentary rock, mixed with the cattle’s manure. This chert was identifiable as originating in Missouri! The suspect denied that his truck had ever been outside the State of Montana. Further study demonstrated that the chert found in the bed of the truck compared with that found at the foot of the cattle loading ramp on the Missouri farm where the cattle had disappeared from. Many pieces of chert had apparently been picked up on the hoofs of the cattle and carried onto the truck during the larceny and remained there until discovered by investigators.

Rocks used to identify drunken shovel operator

Some years ago a gas works in northern Massachusetts experienced what appeared to be repeated acts of vandalism. The coal they used, which was mined in Pennsylvania and transported to Massachusetts by both rail and barge, contained boulders and cobbles of igneous rocks that were destroying the grates in the plant’s furnace. The rocks could have been introduced into the coal from a number of places between the coal mine and the plant. Examination of the rocks showed that they were derived from an area north of the place where the coal was stored near the plant and had markings indicative of having been moved by glacial ice. The glacially-derived soil on which the coal was stored had similar boulders and cobbles. Closer examination of the plant’s coal storage area revealed that their coal shovel operator commonly drank alcoholic beverages on the job. When he was inebriated he tended to misjudge the depth of the coal piles and would inadvertently scoop up some of the underlying glacial till deposits. The situation was quickly remedied.

Soil on tobacco leaves reveals its true identity

In a case of stolen tobacco that was later sold to a warehouse, sufficient soil from the tobacco field had collected on the leaves to permit a study of this soil and samples collected from the fields of the original owner. It was possible to determine that the stolen tobacco had grown in the southern half of one of the original owner’s 10-acre fields. In addition, soil material taken from the leaves of the stolen tobacco was studied along with soil samples taken from fields owned by the suspects. These samples did not compare and their alibi, that it was their own tobacco, was not supported.

Methane detectors can be used to sniff for bodies

A variety of additional techniques is available for the location of bodies in soil. Nonembalmed bodies have been located using instruments that detect the methane gas given off by the decomposing body. Five-foot metal rods are forced into the ground and removed, and the probe of a methane detector is inserted. If the soil contains large amounts of naturally decomposing organic matter, the methane produced by this material will be recorded, and the additional methane produced by a body may not be sufficient to be detected.

How a small bit of soil beneath a burned out car’s fender solved the Adolph Coors kidnapping

The study of soil has often been used on a regional scale to assist an investigation. In the well-known Adolph Coors kidnap and murder case, the victim disappeared one morning near Morrison, Colorado, a town southwest of Denver in the foothills of the Rocky Mountains. His automobile was found with the motor still running. His glasses and splotches of blood were observed at the scene. However, there was no indication of his fate or location. One month later a suspicious vehicle was found burning in a dump in Atlantic City, New Jersey. Soil samples taken from under the fender of this vehicle showed four layers. The outermost and thus the last deposed layer compared with soil samples collected at the entrance to the dump. The three inner layers contained mineral grains characteristic of the Rocky Mountain front area near Denver. Apparently, the car had been driven only on pavement across the country and thus had failed to pick up recognizable soil layers between Colorado and New Jersey. Over 360 soil samples were collected from the Rocky Mountain front area west of Denver in an effort to compare these samples with those found on the burnt automobile. This was an effort to locate the general area where the victim might be found. While this study was in progress, the body of the victim was found by hunters 27 miles south of Denver. Additional study revealed that the second youngest layer of soil from the suspect automobile compared with the scene where the victim was found, and the third layer compared with soil samples taken from the victim’s ranch. The fourth and oldest layer was not comparable with any of the 421 soil samples collected and studied in this case, but probably came from the Denver area. This evidence contributed to a conviction for kidnapping and murder because it was possible to relate the suspect to the burnt automobile and two specific locations in the Rocky Mountains.

Further interesting reading: see John McPhee, 1996, The Gravel Page: The New Yorker (magazine), v. 71, n. 46, January 29, 1996, p. 44-52.

Forensic geology exposes massive cover-up in the Enrique Camarena case in Mexico (1985)

The laboratory of the Federal Bureau of Investigation remains today one of the world leaders in both research and case examination in forensic geology. The 1985 disappearance of U.S. Drug Enforcement Administration agent Enrique “Kiki” Camarena and the subsequent investigation of his murder is an example of the laboratory’s ability to provide significant evidence. Although U.S. concern for Camarena’s disappearance elicited a Mexican government response of “why are you concerned about the loss of one agent, when we lose over 200 each year in the fight against drug trafficking,” the FBI launched a full investigation into Camarena’s death.

FBI special agent Ron Rawalt, a forensic geologist assigned to their Washington, D.C. laboratory, requested soil samples from the body of Camarena and from the location where the body was discovered in the state of Michoacan. There was abundant evidence that the body had been previously buried and exhumed because body fluids from all sides of the body had become intimately intermixed with rock material. This rock material consisted of tan to brown vesicular volcanic ash and rhyolite fragments. Soil samples collected at the scene where the body was “found” in Michoacan contained relatively coarse greenish to black basaltic glass; thus the body had been exhumed and moved to a new location.

With assistance from scientists at the Smithsonian Institution, the FBI forensic geology unit determined that the rhyolite and volcanic ash from the body were consistent with material from the El Tequilla ash flow in the Guadalajara Basin, approximately 100 kilometers to the north. Extensive field studies were made to narrow the location of the original grave site. Several factors were taken into account in the search; specifically, the preserved ash flow needed to be at least 6 to 8 feet thick with rhyolite present, needed evidence of a recent grass burn because of charred plant material, and needed the same mineralogy and size distribution as the material collected from the body. Using these search criteria, the search area was narrowed, and finally cadaver dogs were used to locate the original grave site, which contained rock and mineral samples that compared with the samples removed from the body.

In the analysis, comparison was made involving over 30 characteristics. Analysis of color was not possible because the material removed from the body had been cleaned in an oxygen plasma, thus potentially altering the color. These studies contributed significantly to the development of evidence supporting a massive conspiracy among certain drug traffickers and the Mexican Federal Judicial Police to cover up the torture and murder of agent Camarena.

The Mexican Federal Judicial Police (MFJP), faced with mounting pressure from the U.S. government to investigate Camarena’s disappearance, conspired with drug traffickers to exhume the body and deliver it to a farm in the state of Michoacan. The MFJP then raided the farm, killing all the occupants and announcing that those killed had been responsible for the murder of agent Camarena. The evidence that the body was originally buried in the area of Guadalajara and then exhumed and dropped at the farm in Michoacan exposed the deception of the attempted Mexican cover-up.
After several years and numerous trials, many of those responsible for agent Camarena’s death and the subsequent cover-up were eventually convicted.

Further interesting reading: see John McPhee, 1996, Death of An Agent, in The Gravel Page: The New Yorker (magazine), v. 71, n. 46, January 29, 1996, p. 60-69.


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